Tongcheng-Elong, which is also backed by travel website Ctrip.Com International, is selling about 143 million shares at a price range of HK$9.75-HK$12.65 ($1.24-$1.61), giving it a potential valuation of $3.65 billion, according to a term sheet seen by Reuters.

The company had earlier been seeking to raise up to $1 billion, but weak markets and a slide in Ctrip's share price forced it to slash the size of the IPO, according to Refinitiv publication IFR.

Online parenting firm Babytree Group, backed by Chinese e-commerce giant Alibaba Group Holding, was also due to hold an IPO news conference on Tuesday but cancelled it on the day.

Babytree said it had to reschedule the event due to a "technical issue". It did not elaborate.

Hong Kong has seen a wave of Chinese tech companies seeking to go public this year, with a total of $27.7 billion raised in the financial hub in the first three quarters of the year, an increase of around 300 percent compared to the same period in 2017, Refinitiv data shows.

But markets have been rattled by trade tensions between the United States and China, which have hit emerging markets particularly hard.

Hong Kong's benchmark Hang Seng index is down almost 16 percent this year.

The market slump has prompted many companies to put their IPO plans on hold, such as Tencent's music streaming arm which is still deciding whether to launch its $2 billion IPO this year, according to sources close to the deal.

Tongcheng could raise as much as $268 million if a greenshoe, or over-allotment option, is exercised within one month of the start of trading.

Unusually for a Hong Kong IPO, Tongcheng has no cornerstone investors.

Asked for the reason, Chief Strategy Officer Wu Jiazhu said Tongcheng already had "excellent strategic investors" such as Tencent and Ctrip.Com.

"Our IPO has attracted interest from several long-only global institutional (investors)," Wu said. "We are very confident in completing a good IPO in Hong Kong."

Books are scheduled to close on Nov. 19 and the company is expected to start trading on Nov. 26.

Tongcheng plans to use the proceeds of the IPO to enhance product and service offerings as well as to fund potential acquisitions and investments.

The company made a profit of 194 million yuan ($27.86 million) in 2017, compared to a loss of 2.16 billion yuan in 2016, according to its prospectus.

CMB International, JPMorgan and Morgan Stanley are joint sponsors for the deal.